Sodium Hydroxide → 3-(3-Hydroxy-4-methoxyphenylamino)phthalic acid

Participants

Reaction Steps

A mixture of 3-[3-(tert-butyldimethylsilanyloxy)-4-methoxyphenyl-amino]phthalic acid dimethyl ester (1.0 g, 2.2 mmol) and 3N NaOH (50 mL) in ethanol (100 mL) was heated to reflux for 2 hours. The mixture was cooled, and the solvent was removed under vacuum. The residue was dissolved in water (100 mL), washed with ethyl acetate (3×75 mL), acidified (HCl) and extracted with ethyl acetate (3×75 mL). The combined organic extracts were washed with water (3×75 mL), dried (MgSO4), and evaporated, providing 0.65 g of the product, in 96% yield: 1H NMR (DMSO-d6) δ 3.73 (s, 3H), 6.54 (dd, J=8.5 Hz, J=2.5 Hz, 1H), 6.60 (d, J=2.5 Hz, 1H), 6.86 (d, J=8.5 Hz, 1H), 6.98 (d, J=7.3 Hz, 1H), 7.13 (d, J=7.7 Hz, 1H), 7.30 (t, J=7.9 Hz, 1H), 7.93 (s, 1H).

Provenance & Evidence